DEODORISING FLUIDS ABSORPTION MAT, IN PARTICULAR FOR COFFINS, AND ITS METHOD OF PRODUCTION

Abstract: The invention relates to an absorption mat, comprising at least a biodegradable bottom layer which is impermeable to fluid, a biodegradable intermediate layer with odour-absorbing and fluid-absorbing constituents, and a biodegradable top layer which is permeable to fluid, which absorption mat during decomposition, in particular during incineration, does not release hazardous waste substances, and which absorption mat has an absorbency of at least 4 litres of body fluid per square metre of absorption mat. The invention also relates to the use of an absorption mat as an absorbent layer in a coffin, and to the use of an absorption mat as the removable cover of a bed or seat for humans or animals with incontinence problems, and to the use of an absorption mat as the removable cover of an operating table, dissecting table or stretcher.

Description: DEODORISING FLUIDS ABSORPTION MAT, IN PARTICULAR FOR COFFINS, AND ITS METHOD OF PRODUCTION The present invention relates to the field of removing odour and fluid, in particular odours and fluids coming from human or animal bodies or corpses. It is a known problem that after some time corpses emit unpleasant odours and fluids. Various solutions have been devised hitherto, but they all have certain disadvantages. In particular, there are coffins which have facilities designed to prevent problems with fluids when a corpse is laid out before the burial or cremation takes place. One example of such facilities is the presence of a plastic tray provided with collecting spaces for fluid, or the presence of a double bottom. However, in the first place these do not prevent the odour problem, and when the coffin is moved fluid can still run out of the collecting spaces, with all the unpleasant problems which this entails. Moreover, in the case of cremations, mainly because of the plastic, such facilities also cause a smell problem and other harmful consequences for the environment. Secondly, if large quantities of fluid are present, there is less efficient incineration during cremations, and this can even lead to the risk of explosion, which again inevitably has harmful consequences for the environment. Perfumes are generally used to solve the odour problem, but they are not always effective, since they merely have a masking effect, and they do not prevent the material which is spreading the unpleasant smell from coming into contact with persons in the immediate vicinity, so that when these persons leave the perfumed room an odour problem still arises. Perfumes themselves can also cause allergic reactions and confuse the sense of smell. This is an unattractive solution in particular for persons who are frequently in a room containing such perfumes. Use is also made of ionizers, in which ions of gases are polarized, which means that the odour is dispersed and that the charged ions precipitate on walls, furniture, floor covering and the like, which can lead to discoloration of material. This neither controls the fluid problem nor protects the environment. In French patent application 2 679 ^^ use of a composite material capable of inflating without dissolving in a major manner in the presence of water or water-like solutions comprising a hydroexpansible polymeric powder in linings of coffins is described. Such composite materials are known from the industry of electric cables and are used in the cable envelope. For use in coffins the materials generally comprise a hydroexpansible polymeric powder sandwich between two non-woven layers wherein the cohesion of the composite is obtained by incorporating the hydroexpansible polymeric powder in a thermoplastic substance which becomes soft and sticky under the action of pressure and heat. Non- sandwich like structures are also described comprising a solid flat support with at least one of the phases being a coating comprising a large proportion of the hydroexpansible polymeric powder. Another suitable material comprises one flat fibre-like element without recognizable stratifications containing the hydroexpansible polymeric powder particles. The examples given of the polymeric powders are modified acryl polymers, grafted starch, polyacryl amids, carboxy methyl cellulose. It is also described that the materials can be assembled or stuck to a film with good impermeability characteristics and capable of providing a mechanically acceptable resistance to the assembled article. The material can be selected from films on the basis of biodegradable materials. The described material however is not completely biodegradable as the liquid absorbing part is not biodegradable. Furthermore, the problem of the odour is not addressed in the French application and the mat described therein do not solve the problem. In French patent application 2 635 986 a composition for use in coffins is described comprising adsorbent material, their composition is present in the form of a powder, mini grains or granules forming a homogenous mixture and forming a stable mixture consisting essentially of a mixture of a known absorbent hydroxy ethylated starch and odour producing components and bactericidal agents. In contact with water the absorbent polymer forms a compact gel which is dry to the touch. In order to provide an odour the product comprises a combination of natural essences fixed to a silica support known as such and the capability of diffusion is reinforced by the presence of an isoparaffine solvent with an alkyl chain of C 12 -C 13 . The problem of the odour is described in the French patent application, however, the solution selected has disadvantages. As already stated previously in the introduction the presence of perfume producing products is insufficient to properly solve the problems associated with the bad odour emitting from corpses and bodily products. The French patent application is not directed at a mat as absorbent layer but at beads or grains of gel-like substance. The described composition is therefore not suited for applications other than coffins e.g. on operating tables and beds. In EP 0258 144 a mattress for use in coffins is described directed at solving the problem of the reduced adsorbance due to compression of the mattress when something is placed thereon. The solution proposed consists of a number of layers of cardboard and adsorbent material, also comprising supports thereby reducing the compression of the mattress. The cited European patent application is not directed at reduction of odour and furthermore has the additional problem that the mattress becomes thick and requires more material which increases the production costs. Furthermore, use of such a mattress in hospitals etc. would not be suitable as the waste disposal costs will be higher due to an increased volume of waste. Finally, as the standards existing as regards emission of waste gases from crematoriums have become quite stringent, and with regard to the burial of corpses due to the fact that something which is put in the ground can ultimately come back to man in the food chain or in another way environmental aspects are becoming increasingly important. A solution to both the odour and the fluid problem which also takes account of environmental and cost aspects was sought. The object of the present invention is to solve the problems outlined above. For that purpose, the present invention relates to an absorption mat, comprising at least a biodegradable bottom layer which is impermeable to fluid, a biodegradable intermediate layer with odour- absorbing and fluid-absorbing constituents, and a biodegradable top layer which is permeable to fluid, which absorption mat during decomposition, in particular during incineration, does not release hazardous waste substances, and which absorption mat has an absorbency of at least 4 litres of body fluid per square metre of absorption mat. Numerous examples are known of biodegradable materials which are suitable for the envisaged use in an absorption mat as a bottom layer which is impermeable to fluid. A suitable example is a viscose/cotton non-woven layer which is provided at least on one side with a material which is impermeable to fluid, such as polythene, which can be applied in the form of a film. The top layer of an absorption mat according to the invention can also be made of various materials which are known to a person skilled in the field of absorption and/or permeability of materials. A suitable example for a biodegradable top layer which is permeable to fluid is a non-woven material such as a mixture of cotton and viscose or a polypropylene fibre. The exact composition of the top and bottom layers will also depend on the specific requirements which the end product must meet, such as what load-bearing capacity the absorption mat must have and whether the absorption mat must also be comfortable. The absorption of both odour and fluid preferably occurs in one layer, which makes the manufacture of the present absorption mat simpler and quicker. For odour absorption it is possible to choose from various materials which are not harmful to the environment and which absorb odour. The following biodegradable materials are suitable examples of such odour absorbers: natural fibres, wood shavings, coke, lignite, activated carbon, odour-absorbing granules, natural zeolite and artificial zeolite. In particular, it is preferable to use a zeolite, more especially a natural zeolite, for example Adsorbex® (trade name) , which is commercially available. This material can be used either in granule or in powder form for odour absorption in an absorption mat according to the invention. Adsorbed can absorb carbon monoxide, carbon dioxide, sulphur dioxide, hydrogen sulphide, ammonia, freon, formaldehyde, mercaptans and heavy metals such as copper, mercury, lead and zinc. It also has an ideal absorption capacity for oil, grease, water and other inert liquids. Adsorbex® itself does not contain any other materials or minerals which are harmful to the environment, so that there are no problems as regards using it in an absorption mat according to the present invention. With a view to manufacturing simplicity, and also costs, it is preferable to use a material which absorbs both odour and fluid. As regards fluid-absorbing constituents, various materials which absorb fluid and are biodegradable, without harming the environment in the process, are also known. Examples of such constituents which can be used in an intermediate layer of an absorption mat according to the present invention are: natural fibres, fluid-absorbing granules, gelatin and sodium salts of polyacrylate. The odour-absorbing and fluid-absorbing constituents in an absorption mat according to the patent application are preferably uniformly distributed over the bottom layer and are preferably fixed, so that when the absorption mat is moved no shifting or accumulation of the absorbing material at a particular point occurs. The intermediate layer of an absorption mat according to the invention can also comprise polythene as the material by means of which the absorbent constituents are fixed, and can also serve as the binding material which produces adhesion of the intermediate layer to top layer and bottom layer of the absorption mat. In a special embodiment, with a view to prevention of mercury pollution, selenium or a selenium derivative which can bind mercury can be incorporated in an absorption mat according to the invention. This is important in particular when the absorption mat is being used in a coffin which is to be placed in the ground. An absorption mat according to the invention can be used as an absorbent layer in a coffin, but the absorption mat can be used with equal advantage in a body bag or shroud. A suitable embodiment of an absorption mat according to the invention will have sealed edges in order to prevent leakage from the absorbent material. The absorption mat can also be made in various thicknesses and sizes, which are either predetermined or can be tailor- made. In general, an absorption mat according to the invention will not be narrower than 0.50 metre, and will mostly be longer than 1 metre. A thickness of 1 millimetre can already be sufficient for the envisaged purpose. The fluid-absorbing capacity will depend on the envisaged application, but for use in a coffin, for example, it will have to be sufficient for absorbing over 4 to 5 litres of body fluid, such as blood, per square metre, so that for even the most damaged bodies sufficient absorption is achieved. The absorption mat can be removed from a roll, and the correct size cut off or made the appropriate shape. In general, an absorption mat will be the size of a human body, but it is possible to determine the size oneself after manufacture. Pre-shaped absorption mats with raised edges can also be manufactured; these are suitable in particular for coffins. The absorption mat according to the invention need only be one millimetre to several millimetres thick for it already to have sufficient absorbency to serve as absorbent material for a corpse. An absorption mat according to the present invention can also be used as a removable cover for an operating table, dissecting table or stretcher, or any other place where contact with blood is to be avoided. For this purpose, it is advantageous to use an absorption mat in which at least the top layer is provided with a bacteria-inhibiting or bactericidal layer. Another embodiment which can advantageously be used for this purpose is an absorption mat which has sterilizable constituents and is supplied preferably already sterilized. Such an application of an absorption mat is very hygienic and is also kind to the environment. Only paper rolls or plastic layers are currently obtainable for this application. Paper has only slight fluid absorbency and no odour absorbency. The existing plastic product has the additional disadvantage that it does not absorb fluid, but merely prevents contact between the layers between which it is placed. Another application for an absorption mat according to the invention is as a removable cover for a bed or seat for humans or animals with incontinence problems. Such an embodiment will preferably comprise a thicker and softer material and also absorption material with a finer, softer texture than is required for use under a corpse. An embodiment which can be cut or trimmed to size is highly suitable for the incontinence application in particular. The absorption mat can be supplied in a roll for this purpose. For all embodiments and applications it is possible to make a roll which comprises at least one removable absorption mat according to the invention. In order to minimize costs it is preferable for the mat to be as thin as possible. An absorption mat according to the invention is simple and cheap to produce. The present invention also relates to a method for manufacturing an absorption mat according to the invention. In such a method the constituents of the intermediate layer are applied in powder form to the layer serving as the top layer or bottom layer, which constituents comprise odour-absorbing and fluid-absorbing constituents and polythene powder, and the third layer is then applied, the layer ultimately forming the underside having been or being provided with polythene film, and the three-ply material being subjected to a heat treatment, during which the polythene powder bonds the two covering layers. A person skilled in the art can also easily devise and carry out other methods and additions to the present method, which production methods are considered to fall within the scope of protection of the present invention. An absorption mat according to the present invention offers solutions to problems in the funeral business and in health care. Both odour-absorption and fluid absorption occur, and it is an ecologically sound product. It is sterilizable, user-friendly, and need not take up much space in storage. Moreover, it can be used for various purposes and is very simple and cheap to produce.

Claims: Claims 1. Absorption mat, comprising at least a biodegradable bottom layer which is impermeable to fluid, a biodegradable intermediate layer with odour-absorbing and fluid-absorbing constituents, and a biodegradable top layer which is permeable to fluid, which absorption mat during decomposition, in particular during incineration, does not release hazardous waste substances, and which absorption mat has an absorbency of at least 4 litres of body fluid per square metre of absorption mat, with the proviso that when the odour absorbing constituent is natural fibre the fluid absorbent is not a hydroexpansible polymer powder or a natural fibre. 2. Absorption mat according to Claim 1, in which the bottom layer comprises viscose/cotton non-woven material provided with polythene film applied to one side. 3- Absorption mat according to one of the preceding claims, in which the top layer is formed from non-woven material such as a mixture of cotton and viscose. 4. Absorption mat according to one of the preceding claims, in which the odour and fluid absorption occurs in one layer. 5- Absorption mat according to one of the preceding claims, in which the intermediate layer for odour absorption comprises at least one of the following biodegradable odour absorbing constituents: natural fibres, wood shavings, coke, lignite, activated carbon, odour-absorbing granules, preferably natural zeolite or artificial zeolite. 6. Absorption mat according to Claim 5. in which the intermediate layer for odour absorption comprises the natural zeolite Adsorbex®. 7. Absorption mat according to one of the preceding claims, in which the intermediate layer comprises at least one of the following constituents as the fluid-absorbing constituent: natural fibres, fluid- absorbing granules, gelatin, sodium salt of polyacrylate, silica gel and starch. 8. Absorption mat according to one of the preceding claims, in which the odour-absorbing and fluid-absorbing constituents are uniformly distributed over the bottom layer and are preferably fixed. 9- Absorption mat according to one of the preceding claims, in which the intermediate layer also comprises polythene as the binding material for the odour-absorbing and fluid-absorbing constituents to bottom and top layer, and preferably also for fixing the odour-absorbing and fluid-absorbing constituents. 10. Absorption mat according to one of the preceding claims, in which at least one of the layers comprises selenium or a selenium derivative. 11. Absorption mat according to one of the preceding claims, in which all constituents are sterilizable. 12. Absorption mat according to one of the preceding claims, in which at least the top layer is provided with a bactericidal or bacteria- inhibiting material. 13- Absorption mat according to one of the preceding claims, in which the edges are sealed. 14. Absorption mat according to one of the preceding claims, in which the edges are raised. 1 . Use of an absorption mat according to one of the preceding claims as an absorbent layer in a coffin. 16. Use of an absorption mat according to one of Claims 1 - 14 as a removable cover for a bed or seat for humans or animals with incontinence problems. 17. Use of an absorption mat according to one of Claims 1 - 14 as a removable cover for an operating table, dissecting table or stretcher. 18. Use of an absorption mat according to one of Claims 1 - 14 in a body bag or shroud. 19. Roll of at least one absorption mat according to one of Claims 1 - 14. 20. Method for making an absorption mat according to one of Claims 1 - 14, in which the constituents of the intermediate layer are applied in powder form to the layer serving as the top or bottom side, which constituents comprise odour-absorbing and fluid-absorbing constituents and polythene powder, following which the third layer is applied, while the layer ultimately forming the bottom side is provided with polythene film and the three-ply material is subjected to the passage of heat, during which the polythene powder binds the two covering layers.

Inventors: KLEINSCHMIDT LEENDERT ANTONIUS, KLEINSCHMIDT, LEENDERT, ANTONIUS
Applicants: ECOPRO BV, KLEINSCHMIDT LEENDERT ANTONIUS, ECOPRO B.V., KLEINSCHMIDT, LEENDERT, ANTONIUS
Application year: 1994
Main classification: A61G17
IPC codes: A61G17